FW, I love your explanation. And Condy, I like your take as well. It is not a "will not forgive you" unto DEATH as far as your salvation goes, for we are promised eternal life. But our fellowship with the Holy Spirit will definitely be colder. Remember the parable of the man who owed all that money and was forgiven the debt. He then turned around and prosecuted someone who owed him a small amount of money and was punished by the man who forgave him originally.
But we can not negate the fact that the wages of sin are death, however, so it is not wise to stubbornly remain in willful sin as a Christian but to obey the Holy Spirit when drawn to repentance, as there is a physical price for willful sin. Check out the carnal Christians in 1 Corinthians 5 (NT). Paul warned them of such. I believe that is one way satan is able to put sickness and possibly tragedy upon certain believers, when they remain in willful sin living carnally. But that is another subject.
Listen. Unforgiveness puts our heart in a horrible state, we sense a "cutting off" of fellowship (NOT salvation) and spiritual misery until we repent and forgive. Forgiveness sets us free from being bound to the offense and the offender in an evil way. Unforgiveness opens the door for the enemy to use us for "target practice" for the fiery darts of the wicked. That is ONE door you wanna remain obedient to God and slam that thing shut, for your own peace sake. I also believe you are causing a "log jam" in the spirit as per this verse:
John 20:22-23 "And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost:
Whose soever sins ye remit, they are remitted unto them; and whose soever sins ye retain, they are retained."
When we bless those who wrong us as instructed, blessing flows to us and God deals with the offender. But holding onto unforgiveness causes a blockage in how God has designed to handle these things. We are putting our own fleshly desire for petting offenses and revenge ahead of Gods ultimate plan.
This is the cause of why unforgiveness makes you miserable. Why entertain it then? I know somethings are HARD to forgive, but His grace provides us even that! Ask Him to forgive through you with HIS perfect forgiveness if you are having trouble. He will help you. The Holy Spirit helps us in our infirmities. It is HIS ability we rely on, not our own anyway.
Just BE FREE and keep on truckin' with the Lord! Forgive and it will be well with you. The word of God says its a bad thing, then its a bad thing. So put it behind you and move on. Case closed.